The present invention relates to an optoelectronic assembly for a high-power optical fiber cable, specifically an optical fiber cable made for transmitting power levels up to and exceeding 20 kW. Generally the optical fiber cable has an input end for an incident beam-light and an exit end where the beam-light is leaving the optical fiber. Optical fibers for transmitting high optical power are frequently used in industrial applications. Specifically they are used in cutting and welding operations by means of high-power laser radiation, but also in other industrial applications such as heating, detection or working operations in high-temperature environments this type of optical fibers can be used. By means of the optical fibers it is possible to design flexible manufacturing systems for transmitting the laser beam from the high power laser source to the work piece. An optical fiber typically has an inner glass core and a transparent, surrounding layer, a so-called cladding, which often is made of doped glass. The cladding has got a lower refractive index than the glass core. The function of the cladding is to keep the optical beam confined to the core. The core and cladding can be covered by protective buffer and jacket layers.
With the evolution of high power fiber and disc lasers with high brilliance the power handling capabilities of optical fibers have increased significantly. When designing optical fiber systems for high power laser radiation it is important that the fiber is efficient for transporting the light and to keep the high brilliance of light through the fiber. Working with the high power light from the lasers, the fiber must also stand this high power light during applications, which can give high back reflections back into the system. This put high demands on the design of optical fiber connectors to withstand high power laser light losses. Fibers are terminated in connectors that hold the fiber end precisely and securely to prevent damage to the fiber and fulfil plug and play demands. A fiber-optic connector is basically a rigid cylindrical barrel surrounded by a sleeve that holds the barrel in its mating socket. The mating mechanism can be, for instance, push-and-click, bayonet, or threaded. A typical connector is installed by preparing the fiber end by removing at least parts of the outer layer, clean the glass layer. In some cases a mode stripper is applied to the glass cladding either by chemical etch or by applying a material with higher refraction index than the cladding layer. As a termination in front a glass cylinder is attached to the fiber end. The fiber core and the glass cylinder are in optical contact to prevent losses and reflections in this point. The glass cylinder is coated for the specific wavelength the optical fiber connector is used for.
A problem with high power laser applications is that losses incurred within a connector due to light leaking out of the optical fiber will generate heat. During cutting and welding operations back reflected process light can cause substantial transmission losses in the reverse direction of the optical fiber and can also cause damage to the optical fiber and the connector. Hence, there is a need for an improved connector device, or optoelectronic assembly that is highly accurate and provides a solution that minimises losses. In case losses occur, the design of the optical fiber connector must handle optical losses without damages.